This article explores the narrative potency and ritual efficacy of a medieval Japanese esoteric Buddhist text in relation to the process of awakening and the construction of imperial legitimation, perceived as two interrelated objectives. Entitled the _Kinpusen himitsuden_, ‘The Secret Transmission of the Golden Peak’, the text was written by the Shingon monk Monkan Kōshin in 1337, soon after the outbreak of the civil war, at the stronghold of the southern court in Yoshino. The text is treated here as a (...) complex ritual platform of metamorphosis and empowerment, intermingling the local cultic structure and the esoteric Buddhist ritual stage of the imperial court as well as realities internal and external to the text, which mutually inform and impregnate one another. Focusing on the articulation of a rock—the body/abode of Zaō, a tutelary mountain deity—we explore its transformation from the site of a local legend of apparition into a Buddha, an object of contemplation, the centerpiece of the imperial stage and a mold for the practitioner’s liturgical body, an achievement allowed by the text taken as a transformative agent. We demonstrate that as an epitome of esoteric Buddhist power, Zaō becomes the source of the emperor’s renewed authority as a Buddhist king, and that in turn, the emperor’s participation in the semiotic sphere of the text endows the deity with sovereign power. As such, this article shows that rather than a vessel of knowledge, the text-as-an-event, is a powerful mechanism of transformation. (shrink)